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Message-Id: <20170728070310.4460-2-pbonzini@redhat.com>
Date: Fri, 28 Jul 2017 09:03:09 +0200
From: Paolo Bonzini <pbonzini@...hat.com>
To: linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc: jmattson@...gle.com, wanpeng.li@...mail.com
Subject: [PATCH 1/2] KVM: nVMX: do not fill vm_exit_intr_error_code in prepare_vmcs12
Do this in the caller of nested_vmx_vmexit instead.
nested_vmx_check_exception was doing a vmwrite to the vmcs02's
VM_EXIT_INTR_ERROR_CODE field, so that prepare_vmcs12 would move
the field to vmcs12->vm_exit_intr_error_code. However that isn't
possible on pre-Haswell machines. Moving the vmcs12 write to the
callers fixes it.
Reported-by: Jim Mattson <jmattson@...gle.com>
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
arch/x86/kvm/vmx.c | 52 ++++++++++++++++++++++++++++++++++------------------
1 file changed, 34 insertions(+), 18 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 47c47f09ee90..18a9a1bb3991 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2442,7 +2442,7 @@ static int nested_vmx_check_exception(struct kvm_vcpu *vcpu)
return 0;
if (vcpu->arch.exception.nested_apf) {
- vmcs_write32(VM_EXIT_INTR_ERROR_CODE, vcpu->arch.exception.error_code);
+ vmcs12->vm_exit_intr_error_code = vcpu->arch.exception.error_code;
nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI,
PF_VECTOR | INTR_TYPE_HARD_EXCEPTION |
INTR_INFO_DELIVER_CODE_MASK | INTR_INFO_VALID_MASK,
@@ -2450,6 +2450,7 @@ static int nested_vmx_check_exception(struct kvm_vcpu *vcpu)
return 1;
}
+ vmcs12->vm_exit_intr_error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI,
vmcs_read32(VM_EXIT_INTR_INFO),
vmcs_readl(EXIT_QUALIFICATION));
@@ -2667,7 +2668,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
* reason is that if one of these bits is necessary, it will appear
* in vmcs01 and prepare_vmcs02, when it bitwise-or's the control
* fields of vmcs01 and vmcs02, will turn these bits off - and
- * nested_vmx_exit_handled() will not pass related exits to L1.
+ * nested_vmx_exit_reflected() will not pass related exits to L1.
* These rules have exceptions below.
*/
@@ -8019,12 +8020,11 @@ static bool nested_vmx_exit_handled_cr(struct kvm_vcpu *vcpu,
* should handle it ourselves in L0 (and then continue L2). Only call this
* when in is_guest_mode (L2).
*/
-static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
+static bool nested_vmx_exit_reflected(struct kvm_vcpu *vcpu, u32 exit_reason)
{
u32 intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
- u32 exit_reason = vmx->exit_reason;
trace_kvm_nested_vmexit(kvm_rip_read(vcpu), exit_reason,
vmcs_readl(EXIT_QUALIFICATION),
@@ -8173,6 +8173,29 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
}
}
+static bool nested_vmx_reflect_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason)
+{
+ u32 exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+
+ /*
+ * At this point, the exit interruption info in exit_intr_info
+ * is only valid for EXCEPTION_NMI exits. For EXTERNAL_INTERRUPT
+ * we need to query the in-kernel LAPIC.
+ */
+ WARN_ON(exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT);
+ if ((exit_intr_info &
+ (INTR_INFO_VALID_MASK | INTR_INFO_DELIVER_CODE_MASK)) ==
+ (INTR_INFO_VALID_MASK | INTR_INFO_DELIVER_CODE_MASK)) {
+ struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+ vmcs12->vm_exit_intr_error_code =
+ vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
+ }
+
+ nested_vmx_vmexit(vcpu, exit_reason, exit_intr_info,
+ vmcs_readl(EXIT_QUALIFICATION));
+ return 1;
+}
+
static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2)
{
*info1 = vmcs_readl(EXIT_QUALIFICATION);
@@ -8419,12 +8442,8 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
if (vmx->emulation_required)
return handle_invalid_guest_state(vcpu);
- if (is_guest_mode(vcpu) && nested_vmx_exit_handled(vcpu)) {
- nested_vmx_vmexit(vcpu, exit_reason,
- vmcs_read32(VM_EXIT_INTR_INFO),
- vmcs_readl(EXIT_QUALIFICATION));
- return 1;
- }
+ if (is_guest_mode(vcpu) && nested_vmx_exit_reflected(vcpu, exit_reason))
+ return nested_vmx_reflect_vmexit(vcpu, exit_reason);
if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) {
dump_vmcs();
@@ -9524,12 +9543,14 @@ static void vmx_inject_page_fault_nested(struct kvm_vcpu *vcpu,
WARN_ON(!is_guest_mode(vcpu));
- if (nested_vmx_is_page_fault_vmexit(vmcs12, fault->error_code))
+ if (nested_vmx_is_page_fault_vmexit(vmcs12, fault->error_code)) {
+ vmcs12->vm_exit_intr_error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
nested_vmx_vmexit(vcpu, to_vmx(vcpu)->exit_reason,
vmcs_read32(VM_EXIT_INTR_INFO),
vmcs_readl(EXIT_QUALIFICATION));
- else
+ } else {
kvm_inject_page_fault(vcpu, fault);
+ }
}
static inline bool nested_vmx_merge_msr_bitmap(struct kvm_vcpu *vcpu,
@@ -10863,13 +10884,8 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
vmcs12->vm_exit_reason = exit_reason;
vmcs12->exit_qualification = exit_qualification;
-
vmcs12->vm_exit_intr_info = exit_intr_info;
- if ((vmcs12->vm_exit_intr_info &
- (INTR_INFO_VALID_MASK | INTR_INFO_DELIVER_CODE_MASK)) ==
- (INTR_INFO_VALID_MASK | INTR_INFO_DELIVER_CODE_MASK))
- vmcs12->vm_exit_intr_error_code =
- vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
+
vmcs12->idt_vectoring_info_field = 0;
vmcs12->vm_exit_instruction_len = vmcs_read32(VM_EXIT_INSTRUCTION_LEN);
vmcs12->vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
--
1.8.3.1
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